A Northwest Airlines plane bound for the Twin Cities overflew Minneapolis-St. Paul International Airport by 150 miles Wednesday night, while the pilots engaged in a heated discussion over airline policy, according to federal officials.

The plane landed safely, and none of the 147 passengers or crew members was injured.

The National Transportation Safety Board said the Airbus A320 had departed from San Diego. At 7:58 p.m., the plane flew over the airport and continued northeast for 150 miles.

Air traffic controllers re-established communications with the crew at 8:14 p.m., and asked that the plane return to the Twin Cities.

The flight was 74 minutes late, according to the Northwest Airlines Web site. The site listed the flight as "delayed due to weather-air traffic control." The flight landed at 9:15 p.m.

In interviews with the FBI and airport police, the crew stated they were in a "heated discussion over airline policy and they lost situational awareness," according to the National Transportation Safety Board.

"They probably lost track of where they were," said Keith Holloway, public affairs officer for the NTSB.

Bach Parker, a passenger on the flight, said the pilots came on the intercom twice to announce delays in the forty minutes before the plane landed, but did not state that the plane was off course.

"So it was interesting to hear that we flew into Wisconsin," he said.

Parker said the plane was met by police officers and other officials. He said officials searched the cockpit and removed what appeared to be a plastic box, while the pilots remained in the cockpit.

The pilots "have been relieved from active flying duty pending the completion of these investigations," according to Delta Air Lines, which owns Northwest. Airline officials said they have begun an internal investigation.

Federal officials are in the process of reviewing the cockpit voice recorder and flight data recorder.

Airport spokesman Patrick Hogan said airport officials intervened when the plane landed to make sure that it had not been hijacked. Hogan said the pilots were cooperative with airport officials.